Since the advent of stored-program control, telecommunications networks have been expanding their capabilities and functionality to provide a rich, varied, and flexible menu of telecommunications features and services. In the recent past, this evolution has culminated in the development of the Intelligent Network/2 (IN/2). The IN/2 architecture concept diverges from the traditional new service introduction approach by distributing call-processing capabilities across multiple network modules, by constructing network services with service-independent capabilities, and by using standard signaling protocols among network elements. A thorough overview of intelligent networks is presented in IEEE Communications Magazine, Vol. 26, No. 12 (December 1988) and Vol. 31, No. 2 (February 1992); these issues are dedicated to this subject.
With the evolution of the telecommunications networks and their capabilities have come network-based information-retrieval services which provide on-line, real-time access to information stored in electronic databases. Examples of these are the Dialog.RTM. and Lexis/Nexis.RTM. services and university campus library-access systems. Recently, even more sophisticated network-based educational systems have started to emerge, which facilitate distance learning, interactive distance classrooms, and video-based participation of distant classrooms. Illustrative examples of such systems are proposed and described in F. B. Brown, "A Primer on Telecommunication in Distance Learing", Proceedings of the Pacific Telecommunications Council (Jan. 12-15, 1992), paper no. 2.3.6.1; and P. L. Taylor, "The Global Classroom: A Telecommunications Event for Educators", id., paper no. 2.3.6.2. Nevertheless, all these services and systems have a common shortcoming in that they are essentially passive retrievers and transporters of precisely-specified information, and hence require a high degree of a-priori knowledge and sophistication from their users. The knowledge and sophistication are necessary for the proper formulation of information requests and resultant information searches. In essence, the user must know precisely what information he or she needs, where to find it, and how to ask for it.
The field of artificial intelligence includes among its considerations the representation of knowledge in machine-understandable form, known as knowledge engineering. Excellent overviews of the artificial intelligence field, including of knowledge engineering, are presented by Elaine Rich in Artificial Intelligence, McGraw-Hill Book Co. (1983), and by Edward A. Feigenbaum et al. (eds.) in The Handbook of Artificial Intelligence, Vols. 1-3, Heuris Tech Press/Wm. Kaufmann, Inc. (1981, 1982). Although artificial intelligence has been successfully applied in the field of education, to computer-assisted instruction, little or no work has been done in applying the lessons and techniques of artificial intelligence in general, and of knowledge engineering in particular, to the network-based information-retrieval services.